Tuning Gold Nanoparticles with Chelating Ligands for Highly Efficient Electrocatalytic CO2 Reduction

Article abstract of DOI:10.1002/anie.201805696

Capped chelating organic molecules are presented as a design principle for tuning heterogeneous nanoparticles for electrochemical catalysis. Gold nanoparticles (AuNPs) functionalized with a chelating tetradentate porphyrin ligand show a 110-fold enhanceme

Full text of DOI:10.1002/anie.201805696

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Accepted Article
Title: Tuning Gold Nanoparticles with Chelating Ligands for Highly
Efficient Electrocatalytic CO2 Reduction
Authors: Zhi Cao, Samson B. Zacate, Xiaodong Sun, Jinjia Liu,
Elizabeth M. Hale, William P. Carson, Sam B. Tyndall, Jun
Xu, Xingwu Liu, Xingchen Liu, Chang Song, Jheng-hua Luo,
Mu-Jeng Cheng, Xiaodong Wen, and Wei Liu
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To be cited as: Angew. Chem. Int. Ed. 10.1002/anie.201805696
Angew. Chem. 10.1002/ange.201805696
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10.1002/anie.201805696
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Tuning Gold Nanoparticles with Chelating Ligands for Highly
Efficient Electrocatalytic CO2 Reduction
Zhi Cao+, Samson B. Zacate+, Xiaodong Sun+, Jinjia Liu, Elizabeth M. Hale, William P. Carson, Sam B.
Tyndall, Jun Xu, Xingwu Liu, Xingchen Liu, Chang Song, Jheng-hua Luo, Mu-Jeng Cheng, Xiaodong
Wen* and Wei Liu*
Abstract: We report the capped chelating organic molecules as a
design principle for tuning heterogeneous nanoparticles for
electrochemical catalysis. Gold nanoparticles (AuNPs) functionalized
with a chelating tetradentate porphyrin ligand show a 110-fold
enhancement, compared to the oleylamine-coated AuNP, in current
density for electrochemical reduction of CO2 to CO in water at an
overpotential of 340 mV with Faradaic efficiencies (FEs) of 93%.
These catalysts also show excellent stability without deactivation,
<5% productivity loss, within 72 hours of electrolysis. DFT
calculation results further confirm the chelation effect in stabilizing
molecule/NP interface and tailoring catalytic activity. This general
approach is thus anticipated to be complementary to current NP
catalyst design approaches.
scaffold can maximally maintain the exposed active metal sites
by forming nearly “bare” metal surface, significantly different
from surface functionalized by traditional alkyl surfactants
(Scheme 1).
Porphyrin ligand P1 was prepared following a reported
approach (Scheme 1).[36] Oleylamine-capped Au NPs (OAm-
AuNP) were synthesized according to literature methods.[27, 33]
The ligand exchange step for preparing porphyrin-functionalized
Au NPs (P1-AuNP) was carried out by soaking OAm-AuNP in
50 mM dichloromethane solutions of P1 for 12 h (see SI). P1-
AuNP was collected by centrifugation, and dried overnight for
characterizations. P1-AuNP was then re-dispersed in
dichloromethane and dropcasted on carbon paper for
electrochemistry studies. [28, 33]
Electrocatalytic reduction of carbon dioxide (CO2RR) into
value-added chemicals has emerged as a promising solution for
incremental energy demand.[1-22] Among many electrocatalysts
for CO2RR, metal nanoparticles (NPs) have been extensively
studied due to their high conductivity, large surface area and
high stability under reductive potentials.[23-34] Metal NPs often
possess surfactants with long alkyl chains to stabilize the
surfaces. Nevertheless, these surfactants can block the
catalytically active sites of metal NPs and lower the catalytic
[26-28, 33, 35]
activity.
In addition, the monodentate nature of these
surfactants can result in ligand detachment under the
electrochemical operation, causing particle aggregation and
28, 31, 33]
consequent activity decay.[25,
In this context,
Scheme 1. Synthetic scheme for the preparation of P1-AuNP.
simultaneous stabilization of metal surface and maintaining
catalytically active sites through rational molecular design of
surface capping ligands of NPs is highly desired. We thus seek
to explore the use of a tetradendate ligand that can chelate on
the surface of Au NPs, thereby tuning the CO2RR reactivity and
improving the catalytic stability. We anticipate that this ligand
The successful attachment of P1 to the surface of Au NPs
was first identified by UV-Vis spectroscopy (Figure 1a). The UV–
Vis spectrum of OAm–AuNP displays a characteristic Au NP
absorption at ca. 525 nm,[37] whereas P1 exhibits a strong Soret
band at 425 nm. Upon ligand exchange, the characteristic
absorption peak position red-shifts to 540 nm, retaining a
shoulder peak at 425 nm as the signature of porphyrin Soret
band. In addition, the FT-IR spectrum (Figure 1b) of OAm–
AuNP contains alkyl C-H stretches originated from the surface-
capped oleylamine ligands.[28] The significantly reduced signal of
C-H stretching upon P1 functionalization and the additional
spectral features resembling of the free P1 ligand reveal a close-
to-completion ligand exchange. The peak intensity at 1680 cm-1,
corresponding to the C=O stretches of the thioacetate terminal
group,[38] drastically decreases upon P1 functionalization,
suggesting the in-situ cleavage of the thioacetate groups and
formation of Au-S bonds (Figure 1b). The completion of ligand
exchange was further corroborated by high-resolution N1s and
S2p X-ray photoelectron spectroscopy (XPS). The N1s peak at
[*]
Dr. Z. Cao,[+] X. Sun,[+] J. Liu, Dr. X. Liu, Dr. X. Liu, Dr. C. Song and
Dr. X. Wen
State Key Laboratory of Coal Conversion, Institute of Coal
Chemistry, Chinese Academy of Sciences
Taiyuan, Shanxi 030001 (P. R. China)
National Energy Center for Coal to Liquids, Synfuels China
Technology Co., Ltd,
Beijing, 101400, (P. R. China)
Email: wxd@sxicc.ac.cn
Dr. Z. Cao,[+] Dr. J. Xu
Department of Chemistry, University of California, Berkeley
Berkeley, CA 94720 (USA)
S. Zacate,[+] E. Hale, W. Carson, S. Tyndall, Prof. W. Liu
Department of Chemistry and Biochemistry
Oxford, OH, 45056, United States
Email: wei.liu@miamioh.edu
J. -H. Luo, Prof. M. -J. Cheng
Department of Chemistry, National Cheng Kung University
Tainan 701 (Taiwan)
399.5 eV is consistent with previously reported spectra assigned
39]
to
a
surface-capped porphyrin layer,[36,
revealing the
[+]
These authors contributed equally.
existence of porphyrin on Au surface (Figure 1c) and the minor
peak at ca. 400.3 eV is associated with amide moieties.[40] The
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S2p peak centered at 162.3 eV matches the thiolate peak,[39]
further supporting the Au-S linkages (Figure 1d). High-resolution
transmission electron microscopy studies reveal that P1–AuNP
(Figure 1f, S1b) possesses almost identical morphology to
OAm-AuNP (Figure 1e, S1a). The size distribution analysis
reveals an average particle size of approximately 7.2 nm for
both particles (Figure S2). The crystallinity of the particles is also
similar, as evidenced by X-ray diffraction studies (Figure S3).
Finally, coordination of P1 to the Au surface was verified by solid
state 13C NMR spectroscopy (Figure S4).
We then conducted controlled potential electrolysis (CPE) in
CO2-saturated KHCO3 buffers under different applied potentials
between -0.30 V and -0.70 V to quantify the products of CO2
reduction. Analysis of the head-space and electrolyte solutions
following CPE experiments identified CO and H2 as the gaseous
products for both P1-AuNP and OAm-AuNP. The calculated CO
Faradaic efficiencies (FEs) for both electrodes are shown in
Figure 2b. P1-AuNP shows higher FEs for CO production
compared to OAm-AuNP at all examined potentials. At potential
of -0.45 V, P1-AuNP displays an optimal FE for CO production
(FE = 93%) with a moderate overpotential of 340 mV. By
contrast, OAm-AuNP shows
a FE of only 14% for CO
generation under the same applied potential. Moreover, P1-
AuNP also features significantly enhanced specific current
densities (jCO) of all potential range compared to OAm-AuNP. As
shown in Figure 2c, at the applied potential of -0.45 V, P1-AuNP
exhibits a 110-fold increase in specific CO current density
compared to OAm-AuNP. The striking increase of current
density with P1 ligation implies the superior catalytic activity of
P1-AuNP. As a control, both FEs and jCO of naked-AuNP
(prepared by removal of the surface oleylamine of OAm-AuNP;
details in SI) were also collected and compared under the same
conditions. In brief, naked-AuNP outperforms OAm-AuNP in
terms of both FE and jCO, but is not as robust as P1-AuNP
(Figure S5).
To understand how P1 contributes to the observed
improvements of catalytic activity and selectivity, we first
investigated the electrochemically active surface area (ECSA) of
both OAm-AuNP and P1-AuNP by
a Pb underpotential
deposition (UPD) method (Figure 2d).[28, 33, 41-42] The calculated
ECSA of P1-AuNP is 3.2-fold larger than that of OAm-AuNP,
most likely due to more exposed Au sites as anticipated in ligand
design. To further confirm this hypothesis, we also acquired the
ECSA of naked-AuNP. It turns out that naked-AuNP and P1-
AuNP possess comparable ECSA (1.17:1) and similar TEM
pattern (Figure S6), suggesting that both catalysts expose
similar numbers of Au sites for CO2RR.
Longer-term CPE experiments at the potential of -0.45 V
show that P1-AuNP maintains its catalytic activity and high FE
for CO generation for up to 72 h. In contrast, the activity of
OAm-AuNP drastically lowers in the first 12 h and meanwhile
the FE drops from 62% to ~10% (Figure 2e). As the persistence
of the surface capped or ligated ligands is believed to be crucial
to the associated durability of P1-AuNP,[19-22] we thus further
evaluated the post-electrochemical stability (24 h) of P1-AuNP
by FT-IR, XPS, UPD, and consecutive voltammetry
characterizations. The FT-IR spectrum contains attenuated C-H
stretches at ca. 2900-2700 cm-1, which is likely attributed to
reductive desorption of residual oleylamine ligand present on the
Au surface. In contrast, the IR signals from the ligated P1 (ca.
1800-800 cm-1) remain almost intact (Figure S7). Both N 1s and
S 2p signals are quite consistent with prior features according to
the XPS studies (Figure S8). The decreased intensities of signal
peaks are likely resultant from the detachment of the non-
covalently surface coated porphyrins (either physically adsorbed
porphyrins or stacking of the porphyrins via π-π interactions) or
blockage of the surface sites by residual electrolyte.
Furthermore, the electrochemically accessible Au surface area
of P1-AuNP electrode before and after electrolysis is also similar
as evidenced by the comparable peak areas of Au (111) and
(110) in the UPD studies (Figure S9). Finally, improved durability
of the catalytic interface has been confirmed by the consecutive
voltammetry study[43] under CO2 atmosphere, which showed that
Figure 1. (a) UV-vis spectra of P1, OAm-AuNP, and P1-AuNP recorded in
chloroform. (b) FT-IR spectra of P1, OAm-AuNP, and P1-AuNP. (c) High
resolution XPS spectrum of (c) N1s region and (d) S2p region of P1-AuNP.
TEM image of (e) OAm-AuNP and (f) P1-AuNP, scale bar, 50 nm.
The catalytic activity of P1-AuNP and OAm-AuNP for
electrochemical CO2RR was then studied in a custom-made cell
with 0.5 M KHCO3 as the electrolyte. The current density was
normalized to the geometric area of the working electrodes and
all potentials reported herein are referenced to the reversible
hydrogen electrode (RHE). Cyclic voltammetry (CV) studies
(Figure 2a) have shown that P1-AuNP exhibits significantly
larger total current densities and positively shifted onset
potentials relative to OAm-AuNP electrode. The onset potential
at -0.16 V vs RHE, positively shifted by 290 mV relative to OAm-
AuNP control, reflects a superior catalytic activity of P1-AuNP
for CO2RR in neutral aqueous media.
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the CV curves nearly coincide after 10 consecutive cycles
(Figure S10).
energy of each surface model was computed and converted to
free energy at 25 °C, 1 atm, and −0.11 V, the theoretical
equilibrium potential of CO2 reduction into CO[33, 42] (details in
Supporting Information). The initial step of CO2 hydrogenation
(CO2 + H* → COOH*) to generate COOH*, a key intermediate of
CO2 reduction into CO,[24] is found to be an endothermic process
with a ΔG increase by 0.57 eV on P1-Au(111), compared to 1.12
eV on pure Au(111) surface (Figure 3), suggesting that the
formation of intermediate COOH* is more favorable on P1-
Au(111) surface. Subsequent CO* formation (COOH* → CO*)
on both surfaces is exothermic, along with a lowered ΔG of 0.15
eV and 0.62 eV on P1-Au(111) and Au(111), respectively. This
clearly reflects that the formation of CO* from COOH* is favored
on both P1-Au(111) and Au(111) surfaces. For the elementary
step of CO desorption, only a small energy input of 0.08 eV (P1-
Au(111)) and 0 eV (Au(111)) is associated, indicating a weak
binding of CO on Au surface.[27] Taken together, the catalytic
pathway
predicted
through
theoretical
calculations
unambiguously confirm that the reduction of CO2 to CO on P1-
Au(111) is energetically more favored than Au(111). Overall, we
conclude that the enhanced catalytic performance of P1-AuNP
can be attributed to not only the enlarged ECSA shown by UPD
experiments but also the boosted instrinsic acitivty revealed by
DFT calculation. It is worthy to mention that solvation effect is a
minor factor to our target problem and therefore it has been
neglected in our calculations (Figure S13; details in SI).
Other than the bare Au(111), we were also interested in
acquiring free energy diagram of OAm-coated Au(111) and the
relevant computation was then conducted on a simplified model
of CH3NH2-Au(111) (Figure S14a; details in SI). In brief, the
reaction path monitored on the CH3NH2-Au(111) is also
energetically less favored than that on P1-Au(111) (Figure S15)
in the CO2 reduction to CO. Furthermore, to understand
influence of possible electronic effect, induced by the Au-S
bonding at the interface, on the free energy profile, we have
carried out additional control calculations to probe the free
energy diagram on a simplified model of CH3SH-Au(111) (Figure
S14b; details in SI), which is an effective representative for
monodentate alkylthiol. In short, our results confirm that the
influence of aforementioned electronic effect on the CO2RR path
is trivial (Figure S15). Particularly, the ΔG calculated from the
simplified models is expected to be slightly larger than the real
cases, but the variance is negligible (details in SI).
Figure 2. (a) CV scans of OAm-AuNP and P1–AuNP electrodes under CO2-
saturated 0.5 M KHCO3 at pH 7.3. (b) FEs of CO produced by OAm-AuNP
and P1–AuNP electrodes. (c) Specific current densities of CO generated by
OAm-AuNP and P1–AuNP electrodes. (d) Pb-upd profiles of the OAm-AuNP
and P1–AuNP electrodes in 0.1
M NaOH solution containing 1mM of
Pb(OAc)2, scan rate 50 mV/s. (e) Controlled potential electrolysis of OAm-
AuNP and P1–AuNP electrode at -0.45 V over a 72 h time course. (g) Tafel
plots of OAm-AuNP and P1–AuNP electrodes.
We next explored the kinetics of CO2 reduction on OAm-
AuNP and P1-AuNP electrodes using Tafel analysis (Figure 2f).
The data demonstrates that P1 affects the mechanistic
pathways for CO2 reduction. A Tafel slope of 123 mV/decade is
observed for OAm-AuNP, comparable to what is expected for
rate-determining single-electron transfer (120 mV/decade) from
•- [27, 29]
adsorbed CO2 to generate the surface adsorbed CO2 .
In
contrast, the Tafel slope for P1-AuNP is 69 mV/decade,
reflecting the possibility that P1-AuNP may undergo a pre-
equilibrating one-electron transfer followed by a rate-limiting
chemical step.[28, 31]
Finally, we utilized density functional theory (DFT) and
computational hydrogen electrode calculations on two models of
Au(111) and P1-Au(111) (Figure S11) to further probe the
effects of porphyrin ligation on the Au surface and its reactivity
consequences. We first found that the adsorption of CO2 on
these two models is energetically favored, as evidenced by their
adsorption energy of -0.29 eV for Au (111) and -0.68 eV for P1-
Au(111) (Figure S12). We then calculated the possible pathways
of CO2 reduction into CO on both models. In particular, the total
Figure 3. Free energy diagrams for CO2 reduction to CO on Au(111) and P1-
Au(111).
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[10]
[11]
[12]
N. Han, Y. Wang, H. Yang, J. Deng, J. Wu, Y. Li, Y. Li, Nat.
Commun. 2018, 9, 1320.
X. Liu, J. Xiao, H. Peng, X. Hong, K. Chan, J. K. Nørskov, Nat.
Commun. 2017, 8, 15438.
J. T. Feaster, C. Shi, E. R. Cave, T. Hatsukade, D. N. Abram, K. P.
Kuhl, C. Hahn, J. K. Nørskov, T. F. Jaramillo, ACS Catal. 2017, 7,
4822-4827.
D. Kim, K. K. Sakimoto, D. Hong, P. Yang, Angew. Chem. Int. Ed.
2015, 54, 3259-3266.
J. He, K. E. Dettelbach, A. Huang, C. P. Berlinguette, Angew.
Chem. Int. Ed. 2017, 56, 16579-16582.
A. Loiudice, P. Lobaccaro, E. A. Kamali, T. Thao, B. H. Huang, J.
W. Ager, R. Buonsanti, Angew. Chem. Int. Ed. 2016, 55, 5789-
5792.
H. Wang, J. Jia, P. Song, Q. Wang, D. Li, S. Min, C. Qian, L. Wang,
Y. F. Li, C. Ma, T. Wu, J. Yuan, M. Antonietti, G. A. Ozin, Angew.
Chem. Int. Ed. 2017, 56, 7847-7852.
Z. Weng, X. Zhang, Y. Wu, S. Huo, J. Jiang, W. Liu, G. He, Y.
Liang, H. Wang, Angew. Chem. Int. Ed. 2017, 56, 13135-13139.
L. Zhang, Z. J. Zhao, J. Gong, Angew. Chem. Int. Ed. 2017, 56,
11326-11353.
In summary, we have developed a molecular approach to
tuning the surface properties of metal nanoparticles for
electrocatalysis. The tetradendate ligand enables the formation
of hollow scaffold on gold nanoparticle surface, leaving the
exposed gold sites electrochemically accessible. The prepared
molecular/material hybrid electrode, P1-AuNP, efficiently
catalyzes the reduction of CO2 to CO with a high activity (2
mA/cm2 at 340 mV over-potential) and selectivity (FE = 93ꢀ%).
Furthermore, the catalytic stability is significantly improved by
the chelation effect of the multi-dentate porphyrin ligand, with
negligible decay of FE and current over a 72-hour electrolysis.
Theoretical calculations demonstrate that the reduction of CO2 to
CO on porphyrin-ligated Au surface is thermodynamically more
favored. We envision that tuning heterogeneous nanoparticle
surface with molecularly-tunable multidentate ligands will be a
powerful strategy for the development of novel catalysts for
many sub-fields of heterogeneous catalysis.
[13]
[14]
[15]
[16]
[17]
[18]
[19]
[20]
[21]
[22]
T. Cheng, Y. F. Huang, H. Xiao, W. A. Goddard, J. Phys. Chem.
Lett. 2017, 8, 3317-3320.
T. Cheng, H. Xiao, W. A. Goddard, J. Am. Chem. Soc. 2016, 138,
13802-13805.
R. G. Mariano, K. McKelvey, H. S. White, M. W. Kanan, Science
2017, 358, 1187-1191.
K. Sun, T. Cheng, L. N. Wu, Y. F. Hu, J. G. Zhou, A. Maclennan, Z.
H. Jiang, Y. Z. Gao, W. A. Goddard, Z. J. Wang, J. Am. Chem.
Soc. 2017, 139, 15608-15611.
Acknowledgements
[23]
[24]
Y. Yoon, A. S. Hall, Y. Surendranath, Angew. Chem. Int. Ed. 2016,
128, 15508-15512.
W.L. thanks Miami University for the start-up funding. X.D.W. is
grateful for the financial support from the National Natural
Science Foundation of China (No.21473229 and No. 91545121).
X.D.W. also acknowledges Hundred-Talent Program of Chinese
Academy of Sciences, Shanxi Hundred-Talent Program and
National Thousand Young Talents Program of China.
M. Liu, Y. Pang, B. Zhang, P. De Luna, O. Voznyy, J. Xu, X. Zheng,
C. T. Dinh, F. Fan, C. Cao, F. P. G. de Arquer, T. S. Safaei, A.
Mepham, A. Klinkova, E. Kumacheva, T. Filleter, D. Sinton, S. O.
Kelley, E. H. Sargent, Nature 2016, 537, 382-386.
D. Kim, J. Resasco, Y. Yu, A. M. Asiri, P. Yang, Nat. Commun.
2014, 5, 4948.
Q. Lu, J. Rosen, Y. Zhou, G. S. Hutchings, Y. C. Kimmel, J. G.
Chen, F. Jiao, Nat. Commun. 2014, 5, 3242.
W. Zhu, R. Michalsky, Ö. Metin, H. Lv, S. Guo, C. J. Wright, X. Sun,
A. A. Peterson, S. Sun, J. Am. Chem. Soc. 2013, 135, 16833-
16836.
Z. Cao, D. Kim, D. Hong, Y. Yu, J. Xu, S. Lin, X. Wen, E. M.
Nichols, K. Jeong, J. A. Reimer, P. Yang, C. J. Chang, J. Am.
Chem. Soc. 2016, 138, 8120-8125.
Y. Chen, C. W. Li, M. W. Kanan, J. Am. Chem. Soc. 2012, 134,
19969-19972.
D. Gao, H. Zhou, J. Wang, S. Miao, F. Yang, G. Wang, J. Wang, X.
Bao, J. Am. Chem. Soc. 2015, 137, 4288-4291.
K. Manthiram, B. J. Beberwyck, A. P. Alivisatos, J. Am. Chem. Soc.
2014, 136, 13319-13325.
R. Reske, H. Mistry, F. Behafarid, B. Roldan Cuenya, P. Strasser,
J. Am. Chem. Soc. 2014, 136, 6978-6986.
C. Rogers, W. S. Perkins, G. Veber, T. E. Williams, R. R. Cloke, F.
R. Fischer, J. Am. Chem. Soc. 2017, 139, 4052-4061.
R. Kortlever, I. Peters, S. Koper, M. T. Koper, ACS Catal. 2015, 5,
3916-3923.
W. Zhu, Y.-J. Zhang, H. Zhang, H. Lv, Q. Li, R. Michalsky, A. A.
Peterson, S. Sun, J. Am. Chem. Soc. 2014, 136, 16132-16135.
J. Ohyama, Y. Hitomi, Y. Higuchi, T. Tanaka, Top. Catal. 2009, 52,
852-859.
[25]
[26]
[27]
AUTHOR INFORMATION
Corresponding Author
* wxd@sxicc.ac.cn
[28]
[29]
[30]
[31]
[32]
[33]
[34]
[35]
[36]
* wei.liu@miamioh.edu
Author Contributions
[+] These authors contributed equally.
Notes
The authors declare no competing financial interests.
[37]
[38]
N. G. Khlebtsov, Anal. Chem. 2008, 80, 6620-6625.
A. M. M. Elaasar, C. P. Nash, L. L. Ingraham, Biochemistry 1982,
21, 1972-1976.
Keywords: Electrocatalysis • CO2 reduction • Chelate effect •
Porphyrin • Gold Nanoparticle
[39]
[40]
[41]
K. Masayuki, T. Hirokazu, T. Toshiharu, Angew. Chem. Int. Ed.
2008, 47, 307-310.
S. Govindaraju, S. R. Ankireddy, B. Viswanath, J. Kim, K. Yun, Sci.
Rep. 2017, 7, 40298.
M. Gong, Z. Cao, W. Liu, E. M. Nichols, P. T. Smith, J. S. Derrick,
Y.-S. Liu, J. Liu, X. Wen, C. J. Chang, ACS Cent. Sci. 2017, 3,
1032-1040.
Z. Cao, J. S. Derrick, J. Xu, R. Gao, M. Gong, E. M. Nichols, P. T.
Smith, X. W. Liu, X. D. Wen, C. Coperet, C. J. Chang, Angew.
Chem. Int. Ed. 2018, 57, 4981-4985.
References:
[1]
[2]
H. B. Gray, Nat. Chem. 2009, 1, 7-7.
C. Costentin, M. Robert, J.-M. Saveant, Chem. Soc. Rev. 2013, 42,
2423-2436.
[42]
[43]
[3]
[4]
S. Gao, Y. Lin, X. Jiao, Y. Sun, Q. Luo, W. Zhang, D. Li, J. Yang, Y.
Xie, Nature 2016, 529, 68.
M. Asadi, K. Kim, C. Liu, A. V. Addepalli, P. Abbasi, P. Yasaei, P.
Phillips, A. Behranginia, J. M. Cerrato, R. Haasch, Science 2016,
353, 467-470.
Z. J. Wang, L. N. Wu, K. Sun, T. Chen, Z. H. Jiang, T. Cheng, W.
A. Goddard, J. Phys. Chem. Lett. 2018, 9, 3057-3061.
[5]
S. Lin, C. S. Diercks, Y.-B. Zhang, N. Kornienko, E. M. Nichols, Y.
Zhao, A. R. Paris, D. Kim, P. Yang, O. M. Yaghi, C. J. Chang,
Science 2015, 349, 1208-1213.
[6]
[7]
[8]
[9]
N. S. Lewis, D. G. Nocera, Proc. Natl. Acad. Sci. U.S.A. 2006, 103,
15729-15735.
S. Zhang, P. Kang, M. Bakir, A. M. Lapides, C. J. Dares, T. J.
Meyer, Proc. Natl. Acad. Sci. U.S.A. 2015, 112, 15809-15814.
M. R. Singh, E. L. Clark, A. T. Bell, Proc. Natl. Acad. Sci. U.S.A.
2015, 112, 6111-6118.
H. Xiao, W. A. Goddard, T. Cheng, Y. Liu, Proc. Natl. Acad. Sci.
U.S.A. 2017, 114, 6685-6688.
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Tuning Gold
Zhi Cao+, Samson B.
Zacate+, Xiaodong Sun+,
Jinjia Liu, Elizabeth M.
Hale, William P. Carson,
Sam B. Tyndall, Jun Xu,
Xingwu Liu, Xingchen
Liu, Chang Song, Jheng-
hua Luo, Mu-Jeng
Nanoparticles with
Chelating Ligands for
Highly Efficient
Electrocatalytic CO2
Reduction
Cheng, Xiaodong Wen*
and Wei Liu*
Page No. – Page No.
Gold nanoparticles functionalized with a chelating tetradentate porphyrin ligand exhibit significantly improved catalytic activity
and stability for electrochemical CO2 reduction. The inherent structural and electronic tunability of these prototype
nanoparticles offers an unrivaled degree of control over their reactivity. This approach will be complimentary to current
heterogeneous catalyst design and applicable for various catalytic reactions.
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